Circuit-interrupter.



J. M. WILSON.

GIRGUIT INTERRUPTER.

APPLICATION FILED JUNE 16,1908.

921,046, Patented May 11, 1909.

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APILIOATION FILED JUNE 16,1908.

921 ,046, Patented May 11, 1909.

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5 mm; Wcoz Between the arms of one of the field. magl UNITED STATESPATENT OFFICE.

JAMES M. WILSON, 0F MERIDEN, CONNECTICUT, ASSIGNOR TO THE CONNECTICUTTELEPHONE & ELECTRIC COMPANY, OF MERIDEN, CONNECTICUT, A CORPORATION OFCONNECTIGU'L CIBCUIT-IHTERBUPTER.

v Specification of Letters Patent.

Patented May 11, 1909.

Anliclfilm fled June 16, 1908. Serial No. 438,781.

To all whom it may concern:

Be it known that I, JAMES MI WILSON, a citizen of the United States,residing at Meriden, New Haven county, Connecticut,

have invented certain new and useful Imset up by the magnet of anordinary magneto j and thevariation in the magnetic lines of forceproduced by the rotation of the armature within the held of force of themagnet. It further has for its object to produce a vibrator that isautomatically cut out of action when its prwcnce-is unnecessary, and cutinto action as conditions require.

It further has for its object to produce an interrupter which is readilyaccessible, in I which cams or similar mechanical devices are entirel'done away with, and in which a rubbing e ctrical contact is not reliedupon.

It further has for its, object to produce a device in which theinterruption will be definitely timed. V The following is a descriptionof an embodi ment of my invention, reference being had to S theaccompanying drawings, in which Figure 1 represents an end elevation ofthe magnets and armatin e of a magneto cmbodying my invention, and, insection, the 3 vibrator contacts and their support. Fig. 2 represents alongitudinal section of the magneto onthe line y y Fig. 1. Fig. 3rcpresents a lan view of the magneto. 4 is a mod ed detail. 5 representsa diagram of electrical connections.

Referring more particularlyto the drawgs, A is the armature having polarprojections A A.

BB are field magnets, which are shown as permanent-magnets, asordinarily used in magnetos. V

C-C are portions constituting the'frame which the field magnets aresecured in any. suitable manner, so as to present polar faces to thearmature;

lnets is a bridge or supporting plate D of y non-magnetic material, 111which is placed a screw-plug E having a suitable contact sur-,

face. Above the late or bridge D are two I mainetlc portions F', inclose connection 5 wit the opposite poles of the magnet, and havingbrass stoppers ff to prevent sticking. Above these portions is a secondbridge G, of non-magnetic material, which car- 1 lies a second contactscrew E. The plug E is preferably insulated from the machine at e, butelectrically connected to the plug E l through the switch 6 (Fig. 5).These contact screws E-E, in the form shown, are electrically connectedto each other and to the field magnets through the bridge G. Between thecontact screws and above the magnetic portions F-F is a spring-actuatedmember H supported at its far end at H and l properly insulated. Thismember is of magnetic material, and actuates contacts I i in line withthe contacts E-E', and by its spring qualities is normally held inengagement with the upper stationary contact E. When, however, it issubjected to the magne'tic influence of the magnet, in the mannerhereinafter described, it is drawn down so as to break its enagementwith the up or contact E and m'a lie engagement with t e lowercontact E. The vibrating portion H and the contacts EE' are preferablyshunted by a condenser J and are in series with the armature winding Kand-with the primary of an induction coil L in parallel therewith and aswitch e. The induction coil has a secondary M provided with suitablespark terminals NN for producing a spark upon the interruption of thecircuit at either of the con tacts E E.

The 0 eration of the interrupter is as follows: W on the armature is inthe position i shown inFig. 1, the lines of force from the liield magnetpass through the polar projections. of the armature to such an extent asto 2 have little or no effect upon the sprin 1 restrained contactactuating member l When, however, the armature is revolved islightly, sothat the polar projections are about to pass entirely out of alinementwith the polar faces of the field magnet, the lines in which the armatmeis mounted and to i of force,which have theretofore been shunted by thearmature, pass through the magnetic portions FF an act magnetically uponthe contact-actuating member H, so as to draw it downward, causing theengagement of the contact E to be broken and the\engagement withthecontact E to be made. As the polar projections approach the nextsucceeding polar faces of the field magnet and come into 5 partialalinement therewith, the magnetism of the field magnet is again shuntedby the armature, with the result that the magnetism through the ortionsF falls to such an extent that t ie member H is released, and, beingwithdrawn by the spring action, en-

gagement with the contact E is broken and engagement with the contact Eis made.

, These interruptions of the electric circuitthrough the armaturewinding K in shunt to the coil L act in a well-known way to cause thecurrent through the coil to rise and fall at definite -times, and toinduce an .electromotive force in the secondary winding M. This winding,when properly-proportioned,

will create a sparkin the terminals NN of the spark gap.

It is to be noted that in the apparatus described, the movable contactbearmg member is actuated ma netically in one direction andspring-actuate in the other direction, the movement being produced bythe eriodic shunting of the magnetism of the fie d magnet. This periodicshunting is furthermore due to the movement of the armature'of the maneto. It is further to be noted that for eac alternation of the current,the vibrator will interrupt the circuit twice, once as the polarprojections leave the magnetic fields, and once as they enter themagnetic fields.

If it is desired'to have only one interruption duringl this period, thecontact'E may be remove or disconnected by the switch e It is to benoted that the contacts E and E being stationary, may be made always 40accessible and easily adjustable, even when the magneto is running.

I have shown the movable contacts as insulated, and the plugs E-E asuninsulated from the frame, it being necessary in the form shown thateither the movable or the stationary contact be insulated from theframe.

opening the switch E only one interruption relations this is all that isdesired. When the magneto is speeded up so that the armature revolvessufl'iciently fast, the member H is held away from the upper contact Econtinuously, on account of the short period during which any shuntexists and armature reaction. With this speed, however, theelectro-motive force generated in the armature windings is such that thealternating current produced thereby in the coil duces a secondaryelectromotive force igh enough to produce a flame across the spark gapterminals NN. Thevibrator is thus automatically cut out of actionwhenthe electro-mot'ive force of the armature current When the lower contactis out out by is so high that a make and break is no longer necessary.Conversely, it is automatically brought into action when the armatureelcctro-motive force falls. This automatic cutting out of the vibratorresults in automatically doing away with all the sparking anddestructive action that isordinarily due to the breaking of a circuitcarrying current. At the time the vibrator is cut out, the armaturepotential has becomehigh and the sparking that would be present if theinterrupter remained in action would be particularly disastrous. Whenthe lower contact E is cut out, the interrupter, on account of theconstant spring action, retards the break automatically, so that ittakes place at the most efiicient point of the wave.

In conditions where the current generated is comparatively small, theinterrupter will be operated without a construction employing thewell-known hammer blow feature, and for simplicity I have shown itwithout that feature in the principal figure. I The hammer blowconstruction is shown in Fig. 4, in connection with a single stationarycontact. In this figure, H is a spring magnetic portion mounted prox-'imity to the two extension pieces FF.

'E is a'phosphor bronze spring carrying a contact E engaging astationary contact E and electrical y connected to H When unshunted bythe armature, the portion H is drawn down quickly and hits the spring Ea hammer blow, forcing it away from the contact E thus insuringseparation under all circumstances.

My invention is particularly useful for producing ignition in explosiveengines, the number of poles or the driving connections being. varied soas to produce the roper relative rotations. When the 're ations areproper, the circuit connections can be made as shownin Fig. 5, withoutthe interposition of any timin device, and give the desired sparkspropefiy timed- Various modifications can be made in the embodiment ofmy invention such as will suggest themselves to those skilled in theart, without departing from the broad principle involved.

What I claim is:

1. The combination of a stationary source of continuous magneto motiveforce, a normally retracted movable member attracted by the magnetismproduced thereby, an electric circuit having contacts controlled by saidmovable member, and means for periodically shunting said magnetism awayfrom said movable member.

2. The combination of a stationary source of continuous magneto motiveforce, a movable member attracted by the magnetism produced thereby, anelectric circuit having cooperating contacts controlled by said movablemember, means for periodically shunting said magnetism away from saidmovable member, means for retracting said movable member, said meansalso operating to permit said contacts to remain open for a certainperiodicity of said shunting action.

3. The combination of a field magnet, an armature having polarprojections rotating in the field thereof, a normally retracted movablemagnetic member in a position to be attracted by said field magnet whenits lines of force are unshunted by the armature, and to be releasedthereby when said lines of force are'shunted by the armature, and anelectric circuit including the windings on said armature and contactscontrolled by said movable member.

4. The combination of a field magnet, an armature having polarprojections rotating in the field thereof, a movable magnetic member ina position to be attracted by said field ma net when its lines of forceare unshunted by the armature and to be released thereby when said linesof force are shunted by the armature and an electric circuit includmgthe windings on said armature and Z two contacts, one actuated by saidmovable member and engaging the other when said movable member isretracted, and means for retracting said movable member, said means alsooperating to permit said contacts to remain open for a certainperiodicity of said shunting action.

5. The combination of a field magnet, an armature having polarprojections rotating in the field thereof, a normally retracted movablemagnetic member in a position to be attracted by said field magnet whenits lines of force are unshunted by the armature, and to be releasedthereby when said lines 01 force are shunted by the armature, an electiccircuit including the windings on said armature, and two contacts, oneactuated by said movable member and engaging the other when said movablemember is retracted.

J AMES M. WILSON Witnesses:

R. C. .MITCHELL, H. B. BROWNELL.

